Question

I have a class object that i’m using a lot from different places.

Now i’m using the class like this:

myClass.delegate = self;
[myClass doSomething];

doSomething creates a new class object that calculate stuff and can take up to 1 min before it sends back a result to the delegate like this:

-(void)doSomething {
   CalculateStuff *calc = [[calculateStuff alloc] init];
   calc.delegate = self;
   [calc calculate];
}

/* Calculate Delegate */
-(void)didCalculate {
   [[self delegate] didDoSomething];
}

Problem is that i from another place is calling the same thing it will call my latest delegate and this causes a lot of problems.

Question:

Is there a way to send the delegate as an object without having to set it as the property?
I’ve written it like this and Xcode give me warnings “Incomplete implementation of MyClass”

[myClass doSomethingWithDelegate:self];

And

-(void)doSomethingWithDelegate:(id)delegate {
   CalculateStuff *calc = [[calculateStuff alloc] init];
   [calc calculateWithDelegate:delegate];
}

/* Calculate Delegate */
-(void)didCalculateWithDelegate:(id)delegate {
   [delegate didDoSomething];
}

EDIT
Just tried it out and it seems to work, but how can i get rid of the warnings in Xcode?

Answer 1

I think your problem is that you forgot to remove the declaration of doSomething and didCalculate from your class’s interface (or class extension).

---

Ideally you should create a protocol to ensure that your delegate has the required method(s). For instance:

@protocol DoSomethingDelegate <NSObject>
- (void)didDoSomething;
@end

Then use id<DoSomethingDelegate> instead of just id.

---

Passing a block would also be a valid solution to this problem, although it’s a bit trickier.